chase



A. W. CHASE.. INTERNAL COMBUSTION ENGINE.

l i APPLICATION FILED OCT. I8. 1919.

1,41 1,710. Patented Apr. 4, 1922.

Il' l 0 L' l l I .l 6 l l Il I l O I Il A. W. CHASE. INTERNL COMBUSTIONENGINE.

APPLICATION FILED oc, Ia, 1919. 1,41 1,71() Patented Apr. 4, 1922.

A. W. CHAS'E.

INTERNAL COMBUSTION ENGINE.

- APPLICATION FILED OCT. 18| I9'9. 1,41 1,7 10. Patented Apr. 4, 1922.

Y A. w. CHASE. INTERNAL CONIBUSTION ENGINE. APPLICATION FILED OCT. I8.I9l9.

Patented Apr. 4, 19272.

UNITED STATES leerla:NTA oFFlc;

ALBERT W. CHASE, F CATSKILL, NEW YORK.

vApplication flied-obtener is, 1919.

T0 all wwmfz't may concern: f

Be it known that I, ALBERT W. CHASE, a citizen of the United States,landa resident of the town of Catskill, county of'Greene, and State of New-York, have invented an improvement in Internal-Combustion iEngines, ofwhichthe following is a specification. Y

This invention relates to tion engines. n

An importantobject of the inventionis to provide improved meansforadmitting lthe gaseous charge to the cylinder and exhausting theproductsof combustion therefrom. The character ofthe invention. may bebest understood by reference to the following description ofanillustrative embodiment 'thereof shown in the accompanying drawingswherein like characters refer to like parts throughout' the severalviews.

The engine here shown in which the illustrativek embodiment of theinvention is incorporated is of the four stroke cycle type. F ig. 1 is apartial perspective view, with certain parts broken away to reveal theinterior and certain parts insection, of the engine cylinder with pistonand valves therein. Figs. 2 to 9 inclusive are longitudinal sectionalviews through yone cylinder vatV right angles to the crankshaft with thepiston and valves therein at various positions of their strokes inpassing through the four strokes of explosion, exhaust, charge intake,and compression, the crank rase and contained parts being broken awayin'lig. 2, but shown in section in the remaining figures, and with thecrank at various angular' positions to correspond to the positions ofthe piston.

Referring to the drawings, the illustrative engine there shown comprisesa cylinder 1 somewhat elongatedto provide a slideway for the piston andassociated 'valves below the combustion chamber.'y

lrin-outwardly curved skirt 3, here shown as integral with the cylindercasting, forms the upper portion of the crank case and terminates in arib or flange 4, any suitable means being provided for the convenientattachment and securement of the entire engine structure upon a suitablefoundation or support. Thelower portion 5 of the crank case is attachedto the upper portion 3 and as here shown has a rib or flange abuttingthe riborflanget. vExhaust ports-for the-'eduction of the internalcombus- Specieation vof Letters Patent.

vconcave portion are continued Patented Ape/1, 1922.

seriai No. 331,629.

burnt products of combustion are shown at '7, on opposite sides Yof thecylinder and delivering the products of combustion to an exhaustmanifold 8, in the usual manner.

The cylinder casting extends, upward above the exhaust ports and theexhaust manifold with an interior'diameter uniform with that of thecombustion space, and is closed `by a cylinderfhead casting 9 having adepending cylindrical skirt 10 interiorly spaced from the upper portion'of Vthe cylinder itself toprovidefan annular slideway or guide' for theexhaust valve sleeve later to be more specifically referred to.

The cylinder head casting 9 is continued inwardly and upwardly centrallyof the cylinder in a cup-shaped or concave portion l1 providing aclearance space and ignition chamber 12 opening downwardly into thecylinder, and the walls of the cup-shaped or upwardly in tubular form asshown at 13 for the reception of a spark plug 14, freely insertedtherethrough and secured in exposed position of its sparking points inthe ignition chamber through a screw threaded aperture extending fromthe tubularportion through the end wall of the cup-shaped portion of thecasting, all in the usual manner.V

The customary water jacket 15 is provided around the engine cylindersurrounding the combustion chamber and is extended upward about vtheexhaust manifold and communicates vwith a water jacket 16 in thecylinder head casting, the latter being closed by a.

cap 17 held in place in the usual manner by a screw threaded nut uponthe central tubular portion of the cylinder head casting.

In the illustrative embodiment of my invention here shown!7 thecombustible mixture forming the explosive charge is preferablyintroduced first into the crank case of the engine and thence up throughthe interior of the piston into the cylinder itself where it iscompressed upon the upward stroke of the piston Aand ignited in theusual manner.' lVhen the charge is introduced in this manner, myinvention is particularly applicable to multi-cylinder engines, it beingthe desirable practice to yprovide a common crank case for the severalcylinders, vso that the explosive mixture while in the crank case is notsubject to fluctuating pressures due to the reciprocation of a singlepiston but is at all times at the substantially atmospheric pressure atwhich it entered the crank case,

due to the compensating action of oppositely moving pistons. Thedrawings of the illustrative embodiment f'iny invention show a sectionlongitudinally through one, of such ycylinders and continued through'the con`1` v crank case and its delivery therefrom to the enginecylinders occurs only upon and by reason ofy the creation of pressuresbelow atmospheric in the respective engine -cylinders due to the suctionstrokes ofthe pistons therein, The crank caseI so far as the deliver ofthe explosive mixture to 'the engine cy inders is concerned, therefore,`functions, merelyas a charge inlet manifold.

l To control the delivery` of the explosive mixture to. the enginecylinders and the eductionl of the products of combustion therefrom,charge inlet and exhaust lvalves of novel construction and arrangementyin cooperative` relation with each other and with the'` working pistonare provided, having the advantage among others, ot' being operated bythe direct action of the expanding gases under combustion upon thevalves themselves and by the movement ot the piston acquired by theaction ot' such expanding gasesthereon, and hence requiring no .pmechanically moving parts transmitting tally Aor at Vany desired angle.

movement to the valves from the power shaft orothermoving part of theengine.

-. The illustrative engine here shown is of the vertical cylinder. typealthough my invention is equally applicable toy engines in which thecylinders are disposed horizon- The stroke of the f iston and othermoving parts toward the cylinder head willbe termed their inwardstrokeand their stroke inthe opposite direction will be termed theirv outwardstroke, while location of parts will be defined as inward or outwardrelative totheir positions longitudinally of the cylinder adjacent orremote Jfrom the cylinder head. andthe terms radially inward andradially outward used to define the location oiEk certain partsextending inwardly and outwardly transverselyof the cylinder.

`In the illustrative embodiment. ot the invention shown in the drawings,the valves are in the form of cylindrical sleeves within the enginecylinder. The. exhaust valve, indicated by numeral 22isva thin metalliccylinderor sleeve having oppositely disposed ports 23 near its inwardend to register with the eduction ports 7 thehengine cylinder,

the valve being designed to slidingly engage the interior wall of'` theengine cylinder. The outward limit of movement of the exhaust valve isthat shown in Figs. et and 5 and'in which the ports 23 in the valveregister withthe ports 7 in the engine cylinder. Its inward limit ofmovement is that shown in Figs, 2 3, 6, 71, 8and 9, and in which, itwill be observed, the valve with its ports 23 extendsl into theannularrecess between the cylinder wall 'above the exhaust manifold andthe depending skirt-10 of the cylinder head casting, theexhaust ports 7of the. engine cylinder thus being closed by the imperforate portions ofthe valve sleeve. A packing ring 24 is providedin the depending skirt l0of the cylinder head casting at its lower edge adjacent the` .combustionchamber and bearing radially against .the valvesleeve. ItV is apparentthat with the construction of-valve sleeve and arrange,- ment ofcooperatin vparts suchas the recessed cylinder head with its packing,here shown, pressure leakages from 'the engine cylinder are reduced to aminimum and that ahigh degree of compression is attainable.

The charge inlet valve is also here shown in the form of a Vmetalliccylinder or sleeve 25. ,Charge inlet ports 26 inthe .inlet valve sleevenear its inward edge are provided to register with ports 27 in the,cylindrical skirt of the engine piston just' outwardly ot its head andconstituting delivery passages for the charge fromthe interior of thepiston. The ports in the valve and the piston arev made4 ofsubstantially the same extent circumferentially and preferably aroundthe entire circumfereence of each save for the separating bridge piecesnecessary tomaintain the proper strength of the valve and pistonv as awhole, in order that there may be a rapid delivery or the explosive`mixture and hence a full charge` upon each suction or charging strokeofthe piston. It will be observed that there is no actual delivery oi the.explosive mixture to the combustion space of .the engine cylinder,evenrv though the ports in the valve and piston are in registry, untilthe piston has moved relative to the valve a sufficient distance toposition the piston head outwardlyof the inward edge ot the ports inthevalve, in which relative position Vof the parts the explosive mixturepasses froml the interior of the piston through its ports 27, thence'ittraverses the ports 26 in the inlet valve and is deflected inwardlyacrossthe top of the piston head to the combustion space ofthe4cylinder. The relative Yposition ot the piston andV inlet valvesleeve`obstructing the entrance of a charge. to the combustion space of theAcylinder is shown in Figs. 2, 3,- a, 5,16, and S), while the relativeposition ofthe parts delivering the charge is shown in Figs. 7 and S.

The ports `26. inl the inlet valve sleeve are formed of substantiallygreater extent longitudinally, that is in the direction of movement ofthe piston, than are the ports 27 in the'piston in order that the pistonports may be in register withfthe valve ports and the piston head clearof the inward edge of the valve ports throughout the major portion ofthe movement of the piston relative to the valve which occurs on thesuction stroke of the piston, as will presently be more fully set forth,thus causing a delivery of the explosive mixture throughoutsubstantially the entire suction stroke.

lt will be observed from the cooperative assembly and arrangement of theparts'thus far described that the exhaust valve sleeve must be movedinwardly to close .the exhaust ports and outwardly to open the same andmust be held stationary to maintain the ports in open or closedposition, and that the inlet valve sleeve and piston must be movedrelative to each other in one direction to open the charge inlet portsand in the opposite direction to close the same, and that they mustremain relatively immovable tolmaintain the inlet ports in open orclosed posi'- tion, which obviously means simultaneous movement oftheinlet valve sleeve with the piston. In thefillustrative embodiment of myinvention herev shown the means now to be described are' provided forproducing these relative and' simultaneous movements of the parts. i

The exhaust valve sleeve terminates at its outward end as shown in aradially inwardly projecting ring head or flange 28 having a sliding`engagement upon the exterior cylin-v drical surface of the inlet valvesleeve as shown more particularly in Fig. l, while the inlet valvesleeve has at its inward end a head or flange 29 projecting radiallyoutward to correspondingly engage the interior of the exhaust valvesleeve inwardly of the ring head thereon, as shown more particularly inFigs. 2 to 9 inclusive. The engine piston within the inletvalve sleevehas a portion of such diameter as to slidingly engage the interior ofthe inletvalve sleeve, the relative' movement between these partscontrolling the charge inlet ports as heretofore set forth, and aremaining lower'por tion 30 reduced in diameter,\the two cylindricalportions'of different diameters-being separated by the shoulder 31. Theoutward edge of the reduced portion of the piston terminates inaradially outwardly extending ring or flange 32, shown in the drawingsas a separate piecesecuredto the outward edge or skirt of the piston byscrew threads and which slidingly engages the interior. wall of thecylinder itself. The outward end of the inlet valve sleeve terminates ina ring head having radially inwardly extending flange 33 and radiallyoutwardly extending flange 34, the radially outwardly extending flangebeing here shown as a separate piece screw threaded in place upon thevalve sleeve. The radially inwardly extending flange slidingly engagesthe reduced cylindrical surface 30 of the piston skirtbetween theshoulder 31 and the flange 32while ther radially outwardly extendingflange slidingly engages the interior wall of thecylinder itself.

Bythe arrangement of parts thus described, it is to be observed that theexterior surface of the exhaustvalve sleeve slidingly engages theinterior wall of the cylinder, the radially inwardly projecting annularflange upon the outward end of the exhaust valve sleeve slidinglyengages the exterior cylindrical surface of the inlet valve sleevebetween the flanges 29 and 34 thereon, and the radially inwardlyprojecting flange 33 on the inlet valve sleeve slidingly engages thereduced cylindrical surface of the piston between the shoulder 31v andthe flange 32 thereon, while the interior surface of the inlet valvesleeve slidinglyengages the cylindrical surface of the piston `of largediameter.

It will also be observed that if the parts thus assembled were insufficiently loose. sliding contact to provide a-rapid leakage of theair pressures developed between approaching flanges and shoulders or ifother means, 95 such for example as vent ports, for such leakage wereprovided, the parts may partake of relative movement, `and this relativemovement if of sufficient extent would bring the radially outwardlyextending flanges 29 and 34 on the inlet valve sleeve alternately intocontact with the flange 28`on the exhaust valve sleeveand the shoulder31 and flange 32 on the piston into alternate contact with the radiallyinwardly extending flange 33 on the` inlet va-lve sleeve, thus formingdriving connections between the parts by actual contact, sov that if thepiston be -considered as the prime mover, it would drive the inlet valvesleeve in opposite directions by the alternate engagements. referred toand the inlet valve sleeve thusdriven would in' turn correspondinglydrive the exhaust valve sleeve. s

v Relative movement terminating in a driv` ing connection between theparts is content plated by my invention but preferably actual contact ofthe parts in the driving connec? tion is avoided by the means now to bedescribed.

The piston and inletand exhaust valve sleeves are assembled with theirsurfaces in substantially air vtight sliding contact. grooves areprovided in the recessed or reduced portion of the piston skirt, shownin full outline in Fig. l and in dotted lines in the remaining figures,traversingV 'the greater portion ofthe reduced cylindrical surface inthe line of movement ofthe flange 33 of t-he inlet valve sleevethereover but llO endingl short. ofi the shoulder 31 and the flange -32which determine the vboundaries of the reducedportion of the pistonskirt.

Itis obvious from the arrangement of the grooves that the-piston andinletvalve sleeve may partake off free-relative movement as long as theradially inwardly project-ing receding ring head 33-34' and flange 32,t-he compression occurring between the ring head 33-f34 and the flange32 by their approach to each other 4in the opposite direction ofmovement'being correspondingly relieved through the grooves. When,however, the flange 33 on the inlet valve sleevehas traversed thegrooves to a. pointV closing their outlets at either end, it is obviousthat the air compressed between the oppositely approaching parts has noescape outlet.-l From this point on the.V air is trapped in the space ofdecreasing volume vand an effective air cushion formed preventing actualmetallic contact of the opposed parts but notinterrupting the drivingaction of one upon the other which takes lace through the medium of thethin film o air oir-other gaseousmedium between them. i Grooves 36 arealso rovided in the exterior cylindrical surface o Vthe inlet valvesleeve, corresponding in function to those in the reduced cylindricalskirt of the piston, and extending longitudinally of the sleeve frompoints closely adjacent the flange 34 to and freely opening .into theextended ports in the sleeve, as shown in .full outline in Fig. l and indotted lines in the remaining figures, the ports inthe valve sleevefunctioning, so far asthe equalization of air pressures is concerned, asan extension ofthe grooves. The inletvalve sleeve, it is to be observed,has an ini-perforate and ungroovedport-ion in- Wardly of the inlet portsand immediately adjacent the inward ring head 29 corresponding inlocation and function to the ungrooved portion of Vthe cylindricalsurface between the outward flange 34 and the out- Wardends ofthegrooves 36. As before, it is obvious that the inlet valve sleeve andtheexhaust ,valve sleeve may partake of free relative movementas long asthe radially inwardlyprojecting flange 28 of thev exhaust valve-.sleeveis transversing the. grooves-36 or theports 26 of the inlet valve sleeveforfthe air' or, otherA gaseous` medium lcompressed upon the advancingside ofthe flange 28 is relievedithrough the grooves-36, and ports 26 tothe receding side. When, however,the

flange l28t ofthe exhaust sleeve valve has traversed the grooves orports to a point closing their outlets at either end itis obvious thatan air cushion ivillbe formed between the opposed parts forming adriving connect-ion without actual metallic Contact between them.

Where a vertically disposed cylinderv is` employed as in the`illustrative engine here shown, or VWhere the cylinder is disposed'atany angle to the horizontal, the exhaust and inlet valve sleeves aredesigned to contact With. each other and with the cylinder Wall andtheinlet valve sleeve'ivith the piston with y a Siiflicientfrictional'engagement to main-` tain the sleevesfin elevated positionagainst gravity when the engine is stopped .with the pistonout ofsupporting and driving relation with the sleeves through the flanges alyy The ring head 29 ofthe inlet valve sleeve j is designed 'of such totalsurface transversely of the combustion cylinder as to function asapiston jvvhen impinged upon by the expanding gases upon ignition of thecharge to move the valve simultaneously With and the full length ofmovement of' the piston during i i its ignition or Working stroke. Thismovement-of the inlet-valve sleeve extends from its limit of its stroke,to its position Vshown in Fig. 4, at theoutward limit of its stroke, andthe simultaneous movement of the piston and inlet valve sleeve bothvindependently under the action of the expanding gases during theignition stroke, maintains the piston and surrounding inlet valve sleevewithout relative movement and -With their heads in engagement closingthe inlet pasA sage for the explosive mixture. Y

It `is to `be observed that during afmajoi osition shown in Fig. 2 atthe inwardV poitionloi:l this simultaneous movement of Y the. inletvalve sleeve outwardly With'tlie piston on its ignition stroke, whichsimul taneousmovement maintains the charge inlet closed, the exhaustvalve sleeve must be` stationary to maintain the exhaust ports closed`as shown in Fig. 2, also that at the end of the exhaust stroke and uponthe beginning of the suction stroke, as shown in Fig. 6, when the partsare in the same initial position as at the beginning of the ignitionstroke, and when the piston is about to make itsnextoutvvard stroke,both sleeves must remain stationary, the exhaust valve sleeve tomaintain the exhaust ports all yclosed and the inlet valve sleeve topermit of that relative movement between itself and the piston whichopens the charge inlet ports.

While the valve sleeves `are in frictional contact with each other andwith the cylinder wall and the. inlet valve sleeve is also in frictionalcontact with the piston, as already set forth, such frictional contactis for the purposes already stated and is not relied upon to maintainthe exhaust valve sleeve stationary while the piston and inlet valvesleeve move relatively the-reto upon the'ignition stroke as shown inFig. 2, nor to maintain both valve sleeves stationary while the pistonmoves relatively thereto upon the suction. stroke as shown in Fig. 7. Infact the frictional resistance to relative sliding movement between thevarious parts here described is substantially the same in bothdirections of movement so that its total eifect upon a` change indirection of movement is negligible. The inertia of the valve sleeve tomovement or to change in direction of' movement already acquired is thefactor relied upon to maintain the exhaust valve sleeve stationaryduring movement ofl the inlet valve sleeve with the piston and bothvalve sleeves stationary during the movement of the piston to open andclose the charge inlet ports, within the limits ot' relative movementpermitted by the driving` connections already described. For example,the exhaust valve sleeve having been moved inwardly at piston speed tothe closed position shown inv Fig. 2, and the inlet valve sleeve andpiston having also moved inwardly at piston speed upon the nextpreceding stroke to compress the charge, as will later be more fully setforth` the extremely rap-id change in direction of movement of thepiston and inlet valve sleeve from inward to outward stroke upon theignition of the charge, 'cannot be transmitted to the exhaust valvesleeve in time to overcome the inertia of that sleeve to outwardmovement thro-ugh any other means than a driving connection betweenthem. which as will later be observed, does not occur until the'majorportion of theignition stroke has been performed.

At the beginning of this ignition or workin gstroke. the exhaust valvesleeve, as lshown in Fig. 2, is at the inward limit of its stroke withthe ports 23 therein out of registry with the exhaust ports 7 in theengine cylinder.V Due, as already stated to the inertia of' the exhaustvalvesleeve and the limited Vfreedom of movement permitted. betweenthese valve sleeves, the exhaust valve sleeve remains in its inwardclosing` position while the inlet valve sleeve and piston move outwardlythe ange 28 upon the outward end ot the exhaust valve sleeve describinga relative traversing movement over the exterior cylindrical surfen: ofthe linlet valve sleeve and over the longitudinal pressure equalizinggrooves 36 therein, in the manner already described.

The inward and outward flanges or ring heads on the inlet valve sleeveare so spaced apart and from the flange on the end of the exhaust valvesleeve in the initial position of the valves shown in Fig. 2, relativeto the length of-stroke of' these valves and ot the piston, that uponthe completion of a predetermined portion of the worklngstroke of' thepiston, selected in the illustrative embodiment ot' my invention and asshown in Fig. 3 as three-quarters of the length of' that stroke, theinward ring head 29 of the inlet valve sleeve so closely approaches thelange 28 on the exhaust valve sleeve as to cause the latter to close theinward ends of the grooves in the outer cylindrical surface of the inletvalve sleeve, the ports26 in the inlet valve sleeve here beingconsidered as an extension of the grooves 36. From this point of theignition or working stroke on to its completion the inlet valve sleevedri vos the exhaust valve sleeve through the medium of the entrapped airbetween their opposed flanges .in the manner already described7 theexhaust valve sleeve moving lrom its closed position shown in Figs. 2

and 3 to its open position shown in Fig. 4 with its ports 23 in registrywith the exhaust ports 7 in the engine cylinder. The ignition or workingstroke of the piston has thus been completed and its return stroke toexpel the products of combustion about to begin.

It will also be observed from Fig. 4, that at the completion of theignition or working stroke, the outward ring head on the inlet valvesleeve is in close approach to the flange on the outward end of thepiston skirt with the outward ends of the pressure equalizing grooves 35closed. Upon the inward movement of the piston on its exhaust stroke theair between the flange 32 on the piston skirt and the ring head 33-34 onthe inlet valve sleeve is entrapped andcompressed forming a drivingconnection between the flanges without metallic cont-act in the mannerheretofore described, the piston thus moving the inlet valve sleeveinwardly therewith and to the full extent of the exhaust stroke from theposition shown in Fig. 4 to that shown in Fig. 6. The inlet valve sleeveand the piston still remaining without relative movement.

At the completionof the ignition stroke and the beginning of the exhauststroke, as shown in Fig. 4` the exhaust valve 1s open and its flange 28at the inward end of the cylindrical surface of the inlet valve sleeveremote from the driving flange 34, so thatthe exhaust valve sleeveremains in outward open position while the iston and inlet valve sleeve'travel inward y.,

Because of the relative disposition of the flanges as already stated,the piston driving the inlet valve sleeve inwardly vcompletes the majorportion of its exhaustV stroke, shown in the illustrative embodiment otmy invention as three-quarters of its exhaust stroke, before the flange34.0n the outward end of the inletvvalve sleeve comes into driv- Y ingrelation with the flange 2S on the -end of the exhaust valve sleeve, asshown in Fig. 5. From this point on to the completion of the exhauststroke the piston, inlet valve sleeve .and exhaust valve sleeve move in*wardly in unison, the exhaust valve sleeve movingV to its closingposition shown in Fi .6.

Fig. 6 also shows the position oi' the yparts at the beginning of thenext succeeding' stroke, the suction or charging stroke, and it is to beobserved that there are no flanges in sufliciently close approach Vtoforma driving connection for outward movement of the valve sleeves.During the suction stroke there is, of course, no pressure due to theexpansive force of a gaseousmedium to be exerted either upon the pistonor the ring head of the inlet valve sleeve to drive the same, themovement of the piston being imparted thereto from the crank shaftbecause of the momentum acquired upon the ignition stroke. Because ofthe extremely rapid change iny direction of movement of the piston fromin stroke to out stroke, in effect pulling the piston through the inletvalve sleeve before the change of motion can be imparted to that sleevedue to the inertia of the same, as already stated, the inlet valvesleeve remains inthe position it had attained at the end of the exhauststroke.

`This suction stroke marks the first relative movement between thepiston and the inlet valve sleeve. As soon as the piston passes throughthe inlet valve sleeve a sufiicient distance to expose the piston headoutwardly ofthe inward edge of the ports in the inlet valve sleeve, orotherwise expressed, asufiicient distance to uncover the ports 26,

the carbureter or other charge lforming device and the crank case, whichis in effect so fares the delivery vof the charge is concerned theconnecting charge inlet manifold, are subject to the vacuum created inthe cylinder by the descending piston,and the charge is drawninwardlythrough the interior-ofthe piston, out through the ports 27therein, through the ports 26 in the inlet valve sleeve and yinwardlyover the Vpiston head tothe interior ofthe engine cylinder.`'Filis-.relative movement between the piston and the charge inlet valvesleeve, the valve sleeve remaining, stationary and the pistondescending, continues during an initial portion .of the suction stroke,shown in the illustrative embodiment o-fmy Yinvention as v the firstquarter of ythe suction strokeof the e piston until the sleeve ,landpiston have attained the relative'positionsshown in Fig. 7, and whichmark the fullest extent of opening of the charge inlet valve since thepiston has traversed the ports 26 in the inlet valve and any furtherrelative movement would bring theports 27 inthe piston outl of registrywith the ports in the valve. This position also marks the approach ofthe shoulder'i on the piston into pneumatic driving relation With theinwardly disposed flange 33 on the end of the inlet valve sleeve, andfrom this point on to the end of the suction stroke shownV in Fig. 8,the piston and the inlet valve sleeve move in unison, the relativemovement .of the piston and inlet valve sleeve ceasing so that for theremainder of the suction stroke the inletvalve remains in its fullestopen position relative to the charge delivery ports in the piston, withthe result that the charge is delivered `to the cylinder substantiallythroughout the entire suction stroke of thepiston. f

It is to be observed that during the entire suction stroke from theposition of the parts as shown in Fig. 6 to those as shown in Fig. 8,the exhaust valve remains in its inward closed position due to the factthat the inlet valve sleeve descended With `the piston only duringthelast kportion of its stroke, shown in the illustrative embodiment inF1g.-8 as the last three-quarters of the piston stroke and hence did notmove a sufficient extent to bring its inward ring head 29 into driving.,engagement with the flange on the 'outward endet the exhaust valvesleeve, until the end of thel suction stroke was reached, as shown inFig. 8. 1

The next succeeding stroke of the piston is that compressing the chargeintroduced into the cylinder` and begins from the position of the partsshown in Fig. 8 and ends with the parts in position show-n lin Fig. 2,when the cycle o'lf operations is completed.

Upon the beginning of the compression stroke, as shown in Fig. 8, theoutward flange 32 on the pist'on `is not in driving lrelation with thering head 233-34 on the inlet valve sleeve and does not come intoA suchdriving relation until a portion of the com- Y pression stroke iscompleted, shown in the illustrative vembodiment of my invention asIthat it is this relative movement which closes the charge inlet ports sothat for a brief p0rtion ofthe compression strokeof the Ypiston'A i theinlet ports 4are open. This continuance of the opening of the chargeinlet ports into the ,compression stroke does not, however, re-

dure the total quantity of the charge delivered to the engine cylinderbut rather aug-` ments the same due to the momentum of the rapidlymoving inlet stream.

Upon the completion of this initial portion of the compression strokeand the bringing of the piston to position closing the inlet ports asshown in Fig. 9, the piston and inlet valve sleeve move inwardly inunison for the remainder ofthe stroke due to the approach of theflange-32 of the piston into driving relation with the ring head S3-3aof the inlet valve sleeve.

rIhe exhaust valve, it is to be observed, is not moved during thiscompression stroke from the closedposition it had previously attained,due to the fact that during the movement of the inlet valvefsleeve onthis stroke itsinward flange 29, which forms the only driving member formoving the exhaust valve to open position, is being moved out of insteadof into driving relation with the eX- haust valve sleeve flange 28.

It is obvious that what has beenhere termed the piston with its 'headsubjectto the direct impingement thereon ofthe eX- panding gases ofcombustion and with its ing as and may be regarded as one partof atwo-part charge inlet valve, the second part being the inlet valvesleeve itself.

Obviously the present invention is not limited to the specificembodiment illustrated and described but features of the invention aresusceptible of embodiment in various devices and may be advantageouslyused in various combinations and sub-combinations.

Having now described my invention I claim:

l. In a four stroke cycle internal combustion engine, the combinationwithA a cylinder,

a working piston reciprocating th`erein,vanv exhaust valve and ay chargeinlet valve,

means mounted upon and operated by the piston and mechanicallyoperatingupon the said exhaust and charge' inlet valves to lclose theexhaust valve'on one vstroke of said piston, to-open the charge inletvalve on the next succeeding stroke of saidv piston, and to close-thecharge inlet valve on thesecond succeeding stroke of said piston.

i 2. In a fom-'strokel cycle internal combustion engine, the combinationwith a cylinderY provided with an exhaust port anda charge inlet port, aworking piston reciprocating therein, means mountedV upon and-operated'by the piston to 'close the exhaust port on one stroke of said'piston,to open the charge inlet port on the next succeeding stroke of saidpiston, and to close the charge inlet porton the second succeedingstroke of said piston, said means including exhaust and inlet valves insliding engagement with said cylinder and moved by said piston.

3. In a four strokecycle internal combustion engine, in combination witha cylinder, a single working piston reciprocating therein having acharge delivery passage, a single charge inlet valve mounted forreciprocating movement in'said cylinder and cooperating with said pistonby relative movement therewith in one direction to open said chargedelivery passage and by relative movement in theopposite direction toclose said passage and by lsimultaneous movement with said piston and atpiston speed to maintain said passage open or closed during thereciprocation of said piston, and means for producing said relativemovements in the irectionto open said passage `during the suctionstroke, in the direction to close said passage during the compression"stroke and said simultaneous 'movement' to maintain said passage inclosed position during the explosionv and exhaust strokes.

4. In an internal combustion engine, in combination with' a cylinder, aworking piston reciprocating therein, a two part valvey mounted in 'saidcylinder, the two parts relatively movable inopposite directions insliding engagement-in the line of reciprocation of said piston to openand close said valve and movable simultaneously and together in the samedirection in the line of movement of said piston to maintain said valvein open or closed position, means causing the reciprocation of one ofsaid parts with said piston, driving means associated with said parts in"their closed position and operating only in one direction of movementof said `piston to move said parts simultaneously and-together with saidpiston.

5. In an internal combustion engine,-in combination with a cylinder, apiston reciprocating therein, a two part valve mounted in said cylinder,the two parts relatively movable in opposite directions in the line ofrecipr'ocation of said piston to open or close said-valve and movablesimultaneously and together in the line of reciprocation of saidpistonto maintain said valve in open or closed position, means causingthey reciprocation of one of said parts with said piston, driving meansassociated with'said'partsy in their open position and operating only'inone direction'of movement of said piston to-move said partssimultaneously `andtogether with saidpiston. f. 'i A 6.v In an internalcombustion engine, in combination with a cylinder, aworkin'pistonlreciprocating therein, a two part e arge inlet valve, the -twoparts relatively movable in sliding-engagement in opposite d1- motionsto open and close said yinlet valve,

means associated with said parts limiting their relative movement tocompletely open or completely vclosed position, means causing thereciprocation of one of said parts with the working piston, the other ofsaid parts designed to slidably engage the cylinder walls. v Y

7. 'In a four stroke cycle internal combustion engine, `in combinationwith a cylinder, a working piston reciprocating therein, a two ypartchargekinlet valve, thetwo parts relatively movable in slidingengagement in opposite directions in the line of reciprocation of said.piston to open and close said inlet valve, vand simultaneously movabletogether and in the same direction to maintain saidl valve in Iopen orclosed positionmeans causing the reciprocation of one of said parts withsaid piston, driving means associated with said parts in their closedposition and operating only onthe inward stroke of said piston -to movesaid parts simultaneously and together with said piston.

`8'. In a four stroke cycle internal combustion engine, in'combinationwith a cylinder,

a working piston reciprocating therein, a two `part charge inlet valvethe two parts relatively movable in slidingl engagement in oppositedirections inthe line kof reciproca tion of said piston to Lopen andclose saidrinlet valve, and movable simultaneously and` together in thesame direction in the line of reciprocation of said piston to maintainsaid Vvalve in open or closed positiommeans causing `the reciprocationof one of said parts constantly with said piston, driving meansassociated with said parts in their open .position and operating only onthe outward stroke of said lpiston to move said V.parts simultaneouslyand together with said piston. Y

"9. In a four stroke cycle internal combustion engine in combinationwith a cylinder, a working piston reciprocating therein, a two partcharge inlet valve having ports extending in thefline of reciprocationof said piston `a substantially less distance than the vlength of theiston stroke, the two parts relatively mova le in opposite directions intheV line `of reciprocation of said piston to open and close -said lports, and movable simultaneously` and together in the same -directionin the linerof reciprocation of said piston to maintain'said ports inopen or closed position, means causing the reciprocation of one of saidparts constantly with said piston, .driving means associated withV saidparts in their closed position and open,

ating only on the inward stroke ofsaid piston to move said `partssimultaneously and together withY said piston, driving means associatedwithsaidlpa'rts 1n their open pesitios and operating only onthc outwardstroke of -sald piston to move said parts simultaneously and togetherwith said piston.

10. Inan internal combustion engine, in combination with a cylinder, aworking piston reciprocating therein, a two part charge inlet valvehaving ports extending in the direction of' movement of the piston, asubstantially less distance than the length of the piston stroke, thetwo parts relatively movable in sliding engagement in oppositeVreciprocation of said piston to open and close said valve, means movingone of said parts toward open position of the valve upon eachfoutwardstroke of said piston, the other of said `parts designed to be moved insaid direction of movement of said first mentioned part by the directimpingementv thereon of the expanding gases of combustion.

12. In a four stroke cycle internal combustion engine, in combinationwith a cylinder, a working piston reciprocating thereq in, a two partcharge inlet va ve having ports' extending in the line of reciprocationol:V

said lpiston-a substantially less distance than the length of the pistonstroke,the two parts relativelymovablein sliding engagement in oppositedirections inV the line of reciprocation of said piston to open andclose said ports and movable simultaneously and together in the line kofreciprocation of said piston to maintain said ports in open or closedposition, means causing the constant reciprocation of one of saidpartswith said piston, driving means associated with said parts in theiropen position `and operating only on the outward stroke of said pistonto move said parts simultaneously and to-V gether with said piston,driving means associated with said parts in their closed position andoperating only on the inward stroke of said piston to move said partssimultaneously and together withsaid piston, said valve part notconstantly reciprocating with-V Y' said piston designed to be movedsimultanesVY ouslyv and together with said *pistonV upon its ignitionstrokeby direct impingementof theV expanding gases of` combustionlastfmentioned'valve part. t Y

13.111 an internal combustion engine, in combination with a cylinder,"a. werking on said ing one of said valve parts toward open position ot'the valve upon each outward stroke ot the piston, the other ot saidvalve parts being mounted in sliding engagement with said cylinder walland designed to move in said sliding engagement with said cylinder wallsin the direction of movement of said Y first mentioned valve part bydirect iinpingement on said'other valve part ot the expanding gases otcombustion.

14. In an internal combustion engine, in combination with a cylinder, aworking piston reciprocating therein, a two part charge inlet valve,said parts beingY relatively movable in opposite directions in the lineof reciprocation of said piston to open and close said valve andsimultaneously movable in the same direction to maintain said valve inopen or closed condition, one. of said vvalve parts remaining normallystationary, means moving the other of said valve parts with said pistonwhereby the outstroke o1 said piston relatively moves said parts to openposition and the return stroke of said piston relatively moves saidparts to closed position, the irst mentioned of said valve partsdesigned to be moved simultaneously with said piston upon its ignitionstroke by direct impingement of they expanding gases of combustion onsaid iirst'mentioned valve part. i

15. In Van internal combustion engine, the combination with a cylinder,a combined working and hollow distributing piston reciprocating in saidcylinder and having a piston head and charge distributing ports adjacentthereto, means mounted upon and operated by the combined working anddistributing piston toL expose the charge distributing ports to theengine cylinder on one stroke and to close said chargedistributing portson the next succeeding stroke, said means including a slide valvenormally stationary in sliding contact with said cylinder until moved bysaid piston. 'f K 16. In an internal combustionY engine, in combinationwith a cylinder, a combined working and distributing pistonreciprocating said cylinder having charge delivery ports, an inlet valvesleeve surrounding said piston having ports of greater extent in theline otreffiprocation ot said piston than delivery ports in said pistonbut of substantially less extent thanthe lengthot stroke of said piston,said piston and valve sleeve being relatively movable in slidingengagement in opposite directions in the line ot reciprocation of #aidpiston to open and close said ports.

17. In an internal combustion engine, in combination with a cylinder, acombined working and charge distributing piston reciprocating thereinand having a piston head vnd charge delivery7 ports therewith, a slidevalve sleeve in said cylinder surrounding said working and distributingpiston and having a ring head and ports adjacent 'thereto elongated inthe line of movement ot said piston to extend in the relative openposition of the valve and piston trema point in registry with saiddelivery ports in said piston to a position inwardly and clearingsaid'ring` head :trom said piston head, said piston and valve sleevebeing capable of relative movement from the aforesaid open position toclosed position with said ring head in sliding engagement with saidpiston head, said valve sleeve in the latter relative position oiC theparts designed to partake of a like movement with said piston upon itsignition stroke by direct impingement of the expanding gases ofcombustion upon said ring head.

18. In a tour stroke cycle internal combustion engine, in combinationwith a cylinder, a combined working and charge distributing pistonreciprocating therein having delivery ports tor the explosive mixture,an inlet valve sleeve surrounding said ypiston having ports of greaterextent in the line ot reciprocation oi said piston than said deliveryports in said piston but ot substantially less extent-than the length ofstroke of said piston, said piston and valve sleeve being relativelymovable in sliding engagement in opposite directions in the line ofreciprocation of said piston to open and close said ports, meansassociated `with said piston and valve sleeve limiting their relativemovement to complete open or closed position of said ports,

Vsaid valve sleeve designed to be normally stationary in slicngengagement with said cylinder wall whereby tle reciprocatory movement ofsaid piston opens and closes said ports.

' 19. In a tour stroke cycleinternal combustion engine, in combinationwith cylinder` a combined 'workingl and char-fe distributing pistonreciprocating therein having delivery ports for the explosive mixture,an inlet valve sleeve Asurrounding said piston having ports designed toopen and close communication between said delivery ports and theinterior oit said cylinder. said piston and valve sleeve designed torrelative movement in s diiig'engagement in opposite directions in ytheline ot reciprocation of said piston to open and close saidcommunication, and Jfor simultaneous movement vtogether thereafter tomaintain said piston and valve sleeve in relative positions of open andclosed communication. driving means associated with said piston andvalve sleeve in their closed positionv and operating only in onedirection of movement of said, piston to move said valvesleeve/,simultaneous and together with said piston.

20. In a four stroke cycle internal combustion engine, in combinationwith a cylinder, a Combined Working and charge distributing pistonreciprocating therein having degether to maintain said piston and valvesleeve in relativepositions'of opened and closedy communication, drivingmeans associated with -said piston and said valve sleeve in their openposition and operating only in one direction of movement of said pistonvto move said valve sleeve simultaneously and together with said piston.

2l. In a four stroke cycle internal combustion engine, in combinationwith a cylinder,having an exhaust port, a valve movable to open1 andclose said port, a combined Working and :charge distributing pistonreciprocating therein having 4delivery ports for the explosive mixture,an inlet valve sleeve surrounding said piston having ports designed toOpen and close communication between said delivery, ports and theinterior of said cylinder, lsaid piston andvalve sleeve designed forrelative movement in sliding i l engagement in opposite directions inthe line of reciprocation of said piston to open and -close saidcommunication, andfor simultaneous movement thereafter to maintainsaidrelative positions, means associated with said piston and valvesleeve limiting their relative movement to complete open or closedpositions of said ports, said valve sleeve designed t0 be normallystationary' in sliding engagement vwith said cylinder Wall whereby theinitial movement of. said `piston onthe'suction stroke openssaid portsand the initial movement of said pistonV on its ret-inning stroke closessaid ports, said valve sleeve designed to move initially andsimultaneously with said piston on its ignition stroke by the directimpingement of the expanding products of combustion on said 4valvesleeve, means associated With said valve sleeve. operated by its fulllengthV movement-With Ysaid piston on its ignition stroke to open saidexhaust valve. w22. In a .four strokecycle internal combustionf engine,in combination with a cylinder having an exhaustport, a valve movabletoropen and close said exhaust port, a combined-working and distributingpiston reciprocating in said cylinder, having charge delivery ports, 1aninlet valve sleeve vsurrounding said piston having portsof greaterextent inthe line of reciprocation of said piston than said deliveryports in said piston but of substantially less extent than the length ofstroke of said piston, said piston and valve sleeve being relativelymovable in sliding engagement in opposite directions in the line ofreciprocaton of said piston to open and close 'said ports, said valvesleeve designed to be normally stationary in sliding engagement withsaid cylinder Wall during that part of the piston stroke in eachvdirection required to bring said piston and valve into relativepositions of'open and closed ports, means associated with said pistonandvalve sleeve in the relative'position of open ports to `drive said valvesleeve With said piston on its outward stroke, means associated withsaid piston and valve sleeve in the relative position of closed ports todrive said valve sleeve with said piston on its inf Ward stroke,saidvalve sleeve designed to move insaid sliding engagement with saidcylinder wall. initially and simultaneously with said piston throughoutits vignition stroke by the direct impingement ofV the `expandingproducts of combustion on said valve sleeve, means associated with saidvalve sleeve operated by its full length movement .with said piston' onits ignition stroke to open said exhaust valve, and means associatedWith said valve sleeve operated upon its inward movementivith saidpiston to closevsaid exhaust valve.

23. In a four stroke cycle internal Vcom,- bustion enginepin combinationWith a cylinder,having an exhaust port, avalve movableV to open andclose-said port, a Working piston reciprocating therein, a twopartcharge inlet valve h'avingportsextending in the line of movement of saidpiston substantially a less distance `than the length ofthe pistonstroke, the two parts relatively `movable in sliding engagement inopposite directions in the `line. of reciprocatioh of Said piston Vt0open andclose said ports, means associated Withsaid valve parts limitingtheir relative movement tovcomplete open and closed position of saidports/means causing lthe reciprocation of oneovf/said valveparts with-the Working piston, said other "valve-part vdesigned tobe normallystationary insliding engagement with saidv cylinder Wall during theinitial movement of saidfirst mentioned valve'partfwith said piston -onitsV suction stroke Yto open said ports and during the initial movementof said first mentionedN valve partwith said pistonon its .nextrewherebysaid second mentioned valve part,y

describes strokesin opposite directions less than the correspondingstrokesfoffsaid. pis. ton and first mentioned valvegpart,jsaid secondmentioned valve part designed to move in said sliding engagement withsaid cylinder Wall initially and simultaneously With said pistonthroughout its ignition stroke by the direct impingement of the ex-lpanding products of combustion on said second mentioned valve part,means associated with said second mentioned valve part operated by itsfull length movement With said piston on its ignition stroke to opensaid exhaust valve, and means associated with said second mentionedvalve part and operated by its return stroke With said piston to closesaid exhaust valve.

24. In a four stroke cycle internal combustion engine, the combinationwith a cylinder having an exhaust port, a valve movable to open andclose said exhaust port, a Working piston reciprocating in saidcylinder, means mounted upon and operated bythe piston only on itsexhaust stroke to move said valve to close said exhaust port, and meansoperating independently of said piston only by the expanding gases ofcombustionon the ignition stroke to move said valve to open said exhaustport.

25. In a four stroke cycle internal combustion engine,the combinationwith a cylinder having an exhaust port, a Working piston reciprocatingin said. cylinder, means mounted upon and operated directly by thepiston to close said exhaust port, said means including an exhaust'valvesleeve normally stationary in slidable engagement With said cylinderWall until moved by said pistou only upon its exhaust and ignitionstrokes.

26. In a four stroke cycle internal combustion engine, the combinationwith a cylinder having an exhaust port, a Working piston reciprocatingin'said cylinder, an exhaust valve normally stationary in slidableengagement With said cylinder Wall and movable in opposite directions toopen and close said exhaust port, means mounted upon andV operated bythe piston only on its exhaust stroke to move said exhaust valve toclose said exhaust port, and means operating independently of saidpiston only by thel expanding gases ot combustion on the ignition stroketo move said valve to open said exhaust port. f

27. In a four stroke cycle internal combustion engine, the combinationwith a cylinder having an exhaust port, an exhaust valve sleeve normallystationary in sliding engagement with said cylinder Wall and movable inopposite directions to open and close said exhaust port, a Workingpiston reciprocating in said cylinder, means mounted upon and operatedby said piston on its exhaust stroke to move said exhaust valve sleevetoV close said exhaust port, and means operated only by the expandinggases of combustion on the ignition stroke to move said valve .sleeve toopenv said exhaust ports, said means including a cylindrical sleevemounted in said cylinder and'designed to be frictionally held againstsaid cylinder Wall until moved by the direct impingement thereon of theexpanding gases of combustion.

28. In an internal combustion engine, in combination with the combustionchamber having an exhaust port, a Working piston therein, a valvemovably mounted to open and close said exhaust port, and means operatingon the ignition stroke of said piston to move said valve toopen saidexhaust port and on the next succeeding stroke of said piston to movesaid valve to close said exhaust port, said means including an elementfreely slidable between said piston and saidV valve, designed formovement in the direction of the ignition stroke of said piston solelyby the direct impingement on said element of the expanding gases ofcombustion and means associated with said piston for the return of saidelement to initial position upon the return stroke of said piston.

29. In an internal combustion engine, in combination with the combustioncylinder having an exhaust port, a Working piston reciprocating therein,a valve movably mounted to open said exhaust port in one direction o1movement and to close said exhaust port in the opposite direction ofmovement, an element independently mounted in said chamber for likereciprocatory movement with said piston'designed to be movedsimultaneously with said piston upon its ignitionstroke by directimpingement on said element of the expanding gases of combustion, meansassociated with said piston for the return of said element to itsinitial position upon the return stroke of said piston, and drivingmeans associated with said element imparting reciprocatory movement tosaid exhaust valve.

30. In an internal combustion engine, in combination with the combustionchamber having an exhaust port, a Working piston thereon, a valvemovably mounted to open and close said exhaust port, and means operatingon the ignition stroke ofy said piston to move said valve to Vopen saidexhaust port and on the next succeeding stroke Vof said piston to movesaid Vvalve to close said exhaust port, said means including an elementmounted in and movable in said 'cylinder designed for movement in onedirection to impart closing movement to said exhaust valve by the directimpingement on said element of the expanding gases ot combustion.

3l. In a four stroke cycle internal combustion engine,'in combinationWith an engine cylinder, a Working piston reciproeating therein, acylindrical sleeve element mounted in said cylinder surrounding saidpiston and in sliding engagement With thc walls of said cylinder andpiston, said cylindrical sleeveelement designed to partake of likemovement with said piston upon its ignition stroke by direct impingementof the expanding gases of combustion on said element and meansassociated with said piston returning said element to its initialposition with the return stroke of said piston, an exhaust. valve andmeans to open and close said exhaust valve by the movement of saidcylindrical sleeve element.

32. In an internal combustion engine, in combination with an enginecylinder liaving an exhaust-port, a Working piston reciprocating in saidcylinder. a cylindrical valve sleeve mounted in said cylinder in slidingengagement longitudinally of said cylinder walls to open saidexliaustport by movement in the direction of the ignition stroke of saidpiston and to close said exhaust port by movement in the direction ofthe yreturn stroke of'said piston, a cylindrical sleeve element mountedin said cylinder within said valve sleeve and surroundying said piston,`said cylindricall sleeve element designed to be moved simultaneouslywith said piston upon its ignition Vstroke by direct impingement on saidelement of the expanding products of combustion, means associated withsaid piston for .the return of said element to its initial positionlwith the return stroke'of said piston, and means associatedwith saidelement andV with said valve sleeve to impart like movement from saidelement to said valve sleeve during the latter part of the ignition yandre turn strokes of said element, said means including oppositelydisposed iianges on said cylindrical valve sleeve and on saidcylindrical sleeve element spaced apart a predetermined distance tobring a flange oneacii into driving relation with a flange on Vthe otherjust prior to the completion of the ignition and return strokes of saidpiston and said cylindrical sleeve element.

433. In an internal combustion engine, in combination with an enginecylinder having Van exhaust port, a working piston reciprocatingtherein, a valve closure movable in the direction of the ignition strokeof said piston to open said exhaust port and in the direction of thereturn stroke of saidI pistonv to close said exhaust port, an elementindependently mounted in saidcylinder for like reciprocating movementwith said piston. and designed toV be moved simultaneously7 with saidpiston upon the ignition stroke by direct impingement4 on said elementof the expanding gases of combustion, meansassociated with said pistonfor the return of said element to its initial position with thereturnstroke by saidpistom and means associated with said element andwith said latter part of theignition and return strokes .of saidelement, whereby the. exhaust port is opened during the latter partofthe ignition stroke of said piston and.closed'duringithe latter partof its return stroke.

34k. In an internal combustion engine, in

combination with an engine cylinder, a 'cys lindrical element moving1ltherein undertlie direct impingement thereon of the expanding gasesofcombustion radially outwardlj7 disposed annular projections on thecylindri cal surface of said element spaced apart longitudinallythereof, said cylindrical surface being provided 'with grooves betweensaid annular projections, extending longitudinally thereof andterminating short of the annular projections to provide an annularungrooved portion of the cylindrical surface of said cylindrical elementadjacent each said annular projection, a cylindrical valve sleevemounted in said cylinder, surrounding said cylindrical element andhaving its interior vsurfacein substantially ai r-tight slidingengagement with one of said annular projections on said cylindricalelement, and having a radiallyinwardly disposed annular shoulder. insubstantially airti ghtrsliding engagement with said cylindri# calsurface of said cylindrical `element between said annularvprojectionslthereon.

35. In an internal combustionengine, in

combination with an engineA cylinder, 'a' cy!- lindrical valve sleevemounted' in said cylin# der in frictional sliding Contact with the'cylinder wall, said valve sleevehaving kat one extremity a radiallyinwardly disposed annular flange, a cylindrical elementmoving thereonbythe direct impingement thereon of the expanding gases of combustion,ra-

, annular flange on said valve sleeve, the outer surface of saidcylindricaly element opposed to said valve sleeve having groovesrextending longitudinally thereofjhetween andterf minating shortoffsaidannular projectionsVv thereon to provide ay grooved portion fandVan annular ungrooved portion. of the Ycylindrical surfaceof saidelement` adjacent each said annular projection thereon. Y

36, Inan internal `combustion enginefin combi-nation with fan enginecylinder, a working pistonV reciprocating therein hav` ing a piston headand a cylindrical side wall oftwo portions of unequal diameters sepa-iVrated by an annular shoulder at right angles thereto, and having anannular flange at the outer extremity of the side Wall portion ofreduced diameter, said flange engaging the cylinder Wall in slidingsubstantially air-tight engagement, and spacing said portions of saidpiston Wall of unequal diameters unequal distances from said cylinderWall, a cylindrical valve inlet sleeve surrounding said piston andhaving its interior surface in substantially air-tight sliding con tactWith the cylindrical piston Wall of greater` diameter, said inlet valvesleeve having at one end a radially inwardly disposed annular flange insubstantially airtight sliding engagement With the piston Wall ofreduced diameter7 the cylindrical surface of said piston of reduceddiameter being provided with grooves extending longitudinally thereofand terminating short of said annular shoulder and said annular flangeon said piston to provide an annular ungrooved portion of thecylindrical surface of said piston or" reduced diameter adjacent saidannular shoulder and said annular flange thereon.

In testimony whereof, I have signed my name to this specification, this16th day of October, 1919.

ALBERT W. CHASE.`

